1. Technical Field
A system for linking two or more vehicles to achieve reduced collective aerodynamic drag while the vehicles are travelling on the road is disclosed. The disclosed linking system not only physically connects the vehicles but also allows the driver of the leading vehicle to monitor and control essential functions of the trailing vehicles. Preferably, the driving mechanisms of the trailing vehicles, such as throttles, brakes, and gears, are fully operational so as not to put excessive burden on the driving mechanisms of the leading vehicle. Methods for linking individual vehicles as well as streamlining the operation of a fleet of vehicles are also disclosed.
2. Description of the Related Art
A significant portion of the energy expended by motor vehicles is to overcome aerodynamic drag. In order to improve fuel economy and conserve energy, a wide variety of devices and methods have been developed in the art to reduce aerodynamic drag of motor vehicles. For example, the vehicles may be provided with particularly shaped deflectors, spoilers, side ridges and/or side grooves. Alternatively, the shape of the vehicle or exterior component thereof may be streamlined or rounded. However, those devices or methods are generally directed to improving aerodynamic drag of a single operating vehicle or a tractor trailer assembly, rather than improving collective aerodynamic drag of two or more motor vehicles, each of which independently operational. Further, methods for closely following a motor vehicle are also known in the art. For example, two vehicles may use computer control to maintain their close distance with each other or just draft behind one another to improve aerodynamics. Those methods, however, do not involve the use of a linkage system.
Devices and assemblies for linking two motor vehicles are also known in the art. In particular, when one non-operating vehicle needs to be towed by an operating vehicle to a designated location, the two vehicles may be mechanically connected to each other by simple devices or assemblies, such as tow hitches or tow bars connected to the chassis of the vehicles. In some case, the tow hitches can take the form of a tow-ball to allow swivelling and articulation of a trailer, or a tow pin and jaw with a trailer loop, which are often used for large or agricultural vehicles. A further category is towing pintles used for military vehicles around the world with a hook and locking catch. However, as the non-operating vehicles are almost completely deactivated during towing, none of the known linking devices or assemblies involves the use of an active (e.g. extendable-retractable) member on the trailing vehicle that engages with a passive member on the leading vehicle. Nor is there a known linking mechanism purported to operate two or more motor vehicles to reduce their collective aerodynamic drag.
In addition, towing involves an active, towing vehicle and a passive, towed vehicle. As the driving mechanisms of the towed vehicles are generally deactivated during towing, the driving mechanisms of the towing vehicles, such as the throttles, brakes and gears, inevitably incur excessive wear and tear, which may adversely affect the overall performance, energy efficiency, and service life of the two connected vehicles.
As an improvement of the aforementioned deficiencies, self-propelled trailers have been developed in the art. The trailers may include a slave power source, such as an internal combustion engine, to supply driving force to its wheels. When coupled to a tractor, the self-propelled trailer improves the collective energy efficiency of the tractor-trailer tandem. However, the slave power source of the trailer may only operate to supplement the tractor and generally does not operate to drive the trailer alone without the tractor.
Hence, there is a need for a linking system or method that links two fully operational motor vehicles for reducing their collective aerodynamic drag. Moreover, there is a need for a linking system or method that allows the driver of the leading vehicle to monitor and control the essential driving mechanisms of the trailing vehicle. Further, there is a need for a linking system that connects or disconnects two or more motor vehicles in motion. Finally, there is a need for streamlining the operation of a fleet of vehicles by optimizing their travel route so that linking of vehicles and reducing of collective aerodynamic drag can be maximized.